I have had this tank for almost 20 years. This past June I tore it down so I could reseal it because algea had worked its way between the silicone and the glass. So I did my first reseal job and let it sit without water in it for a month in the garage. I filled it in the garage and let it sit for another month. I brought it back into my fish room did the hardscaping and filled and let the filter run. Still not to confident it wouldn't spring a leak I let it sit on the stand for another 3 months. Well last Saturday I finally got sick of seeing an empty tank and started planting it. Current plants in the tank are a few piece of Anacharis, Duckweed, Dwarf Sagittaria, Giant Hygrophila, Green Cabomba, and some Jave Fern I transplanted from the 29 gallon I set up so this one could be repaired. I still haven't found a piece of driftwood that I like. I also haven't been able to locate any pigmy chain sword locally either.

Front View

Left Front View

Right Front View
NOTE: What looks like algea on the upper ends of the glass is actually a reflection of the duckweed floating on the watesr surface.

I like that. I see what you mean about a piece of driftwood, a largish piece vertical would really complete the scape. If you want fish suggestions, post your water parameters; I can think of lots of combos for that tank.

The aquarist is one who must learn the ways of the biologist, the chemist, and the veterinarian.[unknown source]

Something we all need to remember: The fish you've acquired was quite happy not being owned by you, minding its own business. If you’re going to take it under your wing then you’re responsible for it. Every aspect of its life is under your control, from water quality and temperature to swimming space. [Nathan Hill in PFK]

Those are pretty good numbers. Hardness is around 7-8 dGH, and KH (Alkalinity) is 5-6 dKH. That is in the soft to medium hard range.

You could do basic water fish: livebearers, rainbowfish (Atherinids) and some of the Cyprinids prefer this range, some characins and catfish will manage fine.

Over time I would expect the pH to lower, this depends upon the tank's biology, and you could probably speed it up with half pure water (rainwater if safe where you are, distilled or RO water). This would make it easy for some softer water fish among the Characins and Cyprinids.

Have a look through our fish profiles (second tab from the left in the blue bar across the top of the page), check under Cyprinids, Characins, Livebearers, Catfish. Preferred water params are included for each species, along with minimum tank sizes, compatibility, etc. I would go with generally smaller fish in an hexagonal taller tank, rather than active swimming fish that need length more than height. So among the rainbowfish for instance, the Threadfin wold be a better fit. All of the pencilfish among the characins would suit this type of tank, just watch the water parameters. Hatchetfish (also characins) at the surface will provide interest up there, even more important in taller tanks where the surface can be "bare." For the substrate, corys (under Catfish) will work, or one of the dwarf species of loach (Cyprinids). A whiptail Catfish would be well suited. This should start you.

The aquarist is one who must learn the ways of the biologist, the chemist, and the veterinarian.[unknown source]

Something we all need to remember: The fish you've acquired was quite happy not being owned by you, minding its own business. If you’re going to take it under your wing then you’re responsible for it. Every aspect of its life is under your control, from water quality and temperature to swimming space. [Nathan Hill in PFK]

Over time I would expect the pH to lower, this depends upon the tank's biology, and you could probably speed it up with half pure water (rainwater if safe where you are, distilled or RO water). This would make it easy for some softer water fish among the Characins and Cyprinids.

If I sped up the tanks biology with half pure water now wouldn't I have to continue that process with every water change?

Thank you for the suggestions. I have been looking through the profiles for hours now. Also I have noticed in the profiles they do not list kh numbers, just the ph, so should I use the ph from the cities water parameters I posted as a guide line or the actual water parameter of what is in the tank?

If I sped up the tanks biology with half pure water now wouldn't I have to continue that process with every water change?

Thank you for the suggestions. I have been looking through the profiles for hours now. Also I have noticed in the profiles they do not list kh numbers, just the ph, so should I use the ph from the cities water parameters I posted as a guide line or the actual water parameter of what is in the tank?

Thank you

Most of the freshwater fish profiles are/were written by me, or revised by me. I include GH because it affects fish. KH has no effect whatsoever on fish so it is obviously meaningless in the context of this or that fish's water requirements. The KH of the source water (tap usually) is important for the aquarist to know because it buffers the pH and attempts to adjust pH will fail if the KH is not understood and dealt with if necessary, and a low KH will result in a lowering pH over time.

The tank's biology will settle as the tank matures, and the KH plays a role in this. The lower the KH, the more the water will acidify (with lowering pH). Several factors affect this so it is basically unique with each aquarium. The GH and pH range for each species is rather important, although I appreciate there are differing views among hobbyists on this point. But if one wishes to maintain soft water fish at their best, it is necessary to manage the water parameters somewhat according to their preferences.

Turning to your specifics, the water should acidify over time as the biological system becomes established. Assisting it initially as I previously suggested is what I would do. Once settled, it has a tendency to stay there, especially if one leaves nature alone to do it's thing. Water changes can be experimented with to find the point where minimal impact is achieved. All depending upon one's choice of fish of course.

The aquarist is one who must learn the ways of the biologist, the chemist, and the veterinarian.[unknown source]

Something we all need to remember: The fish you've acquired was quite happy not being owned by you, minding its own business. If you’re going to take it under your wing then you’re responsible for it. Every aspect of its life is under your control, from water quality and temperature to swimming space. [Nathan Hill in PFK]

Last Saturday I finally found a piece of driftwood that I thought would look good in the tank. The lfs has a tank like this one on the floor for sale so I was able to put in in the display tank to try and visualize how it would look. It look narrower in the lfs tank than in my tank but I still do like it. I think there may be some magnification due to the water.

Today I did a 25% water change and replanted some of the plants that were uprooted from putting in the driftwood. But anyways that 25% water change equated to 13 gallons. When I refilled the tank I used 10 gallons of distilled water from the local grocery store and the other 3 from the tap.(I wanted to do 15 gallons of distilled but 10 is all the grocery store had) How long should I wait to retest the water parameters to see what kind of changes it made to the waters chemistry?

Hardness would have been reduced immediately. The pH will initially be that of the source water and as the tank's biological system operates the pH will adjust accordingly. I would test pH daily for a week to see how it is reacting. One would expect it to lower. Always test pH at approximately the same time each day; there is a natural diurnal variation--the pH will be lowest at dawn after the period of darkness, and highest at dusk after the period of daylight. Testing at the same time, whenever, each day will provide a more accurate sense of any pH movement outside of this diurnal variation. I also prefer testing during daylight so I can use natural light (but not direct sun) which will give a better rendition of colour. Most artificial light can alter the colours on the card.

The aquarist is one who must learn the ways of the biologist, the chemist, and the veterinarian.[unknown source]

Something we all need to remember: The fish you've acquired was quite happy not being owned by you, minding its own business. If you’re going to take it under your wing then you’re responsible for it. Every aspect of its life is under your control, from water quality and temperature to swimming space. [Nathan Hill in PFK]